Summary form only given. The wire ion plasma source (WIPS) has thepotential as a high-density-plasma source and a large-cross sectionalion source that can be used for the secondary emission electron gun. Thesecondary emission electron gun of this type usually operates under thepulse mode and is suitable for high repetition rate operations. The WIPSis a cold-cathode gaseous discharge device based on the low-pressurewire discharge. The anode is a thin tungsten wire (Φ0.2 mm). Thecathode consists of a stainless steel cylinder (40 mm i.d., 100 mm long)which is set coaxially to the wire anode and the plates having centralapertures (Φ20 mm) at both ends. This configuration produces notonly a radial logarithmic trapping potential but also an axial one forelectrons, and permits low-pressure (~10-2 Torr in helium)gaseous discharge to occur with very low applied voltage (~1 kV). Pulseddischarges were accomplished by firing a capacitor bank of 24 nF. Thecharging voltages of the capacitor bank. were 3~10 kV. The voltages wereusually fed to the anode wire through a thyratron switch which has ashort life time. So we developed a new method of initiating the pulseddischarge, which is accomplished by controlling the axial trapping ofelectrons
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